An electronic impedance device conventionally used in, for example, a Dolby noise reduction system of a magnetic-tape audio and/or video reading and reproducing apparatus has a drawback in that the device is required to operate on relatively high voltages to compensate for the voltage drops caused across the p-n junctions in the semiconductor elements such as the transistors and diodes. Such an impedance device is not adapted for integration of the semiconductor circuit. The present invention contemplates provision of an electronic impedance device operable on reduced voltages.